1. Field of Invention
This invention relates to pipe connections through which lengths of piping can be coupled into a pipe system for use particularly, but not exclusively, in a mobile structure, for example a caravan, or a boat. The connections are couplings which may be in any form, for example straights, elbows or T-junctions, with each coupling having one or more socket ends into each one of which socket ends a leading end of a length of piping is fitted.
2. Summary of the Invention
Accordingly, the present invention is a pipe connection having a coupling with one or more socket ends defined by a circumferential wall surround in which a plurality of spaced apertures are provided, an annular seal provided at the inner end of each socket end and a collet for location in each socket end, each collet having a corresponding plurality of spaced resiliently mounted legs to the plurality of apertures, the legs being co-parallel with the axis of the collet and having similar barb portions each to enter and be held in a corresponding aperture of the respective socket end whereby to hold the collet, and therefore the seal in position in the socket end.
Each collet preferably has two similar rings, an inner ring and an outer ring, spaced apart axially and held together by a series of posts forming a cage which rigidly supports the piping. Between each two adjacent posts and the rings, a window is beneficially defined in which one of the legs is positioned, the leg being rooted to the outer ring with the leg extending towards the inner ring. A collet is desirably intended for positioning in the respective socket end with the distal ends of the legs directed innermost and with the inner ring innermost. The outer ring beneficially is an angular flange which overlies the outer end of a socket end into which a collet is fitted. The portion of the inner ring in each window has preferably a castellation extending into the window and whose purpose is to restrict inward movement of a respective leg beyond a predetermined limit.
The barb portion for each leg preferably has an outward downwardly sloping face, and an inward radial face, the sloping face commencing inward of the outer ring inclining to stop short of the outer edge of the radial face to form a ledge, the barb portion, when engaged in an aperture, preventing removal of the collet from the respective socket end. Each leg is similar and its inner face may be radially curved along its length.
An inner part of the socket end preferably is of reduced diameter with a first shoulder provided against which the collet lies. The seal may be an O-ring provided to seat between the shoulder and the inner ring of a respective collet.
Preferably, the wall surround of the socket end towards the end face is cut-away between the outer and inner edges of the wall surround to provide an inwardly sloped guideway leading inwards to assist in a riding movement of the outer end of the radial face of the barb portions of the legs into the socket end, the riding movement flexing the legs inwardly with the legs returning to their normal position when the barb portions enter respective apertures. The sloped guideways are desirably radially offset from the apertures requiring the collet to be inserted then rotated for the barb portions to be aligned with and enter the corresponding apertures. The portions of the inside of the wall surround of the socket end between the end face and each window is beneficially provided with a swelling.
Preferably also, each leg has on its inner face opposite to the barb portion, a gripping edge. The gripping edges of the legs together form a broken internal circumferential zone for gripping the outside face of a leading end of a length of piping. The inner edge of the radial face at its junction with the inner face of each finger forms a heel, the heels of the fingers forming a second broken internal circumferential zone. Each leg is desirably provided with a knee at the start of the sloping face of the barb portion and extending along the barb portion a predetermined distance.
Each coupling, collet and piping are preferably of rigid material, either of synthetic plastics material or of a metal or of a metal alloy. The piping of semi-rigid plastics material allows the gripping edges to bite into its surface. However, if the piping is of a rigid plastics material, a metal or a metal alloy, two spaced annular recesses are provided into which the gripping edges and heels locate.
Preferably further, a tubular cover is provided to be located around each socket end to close off the apertures. The end of the tubular cover at the outer ring is beneficially extended and scalloped to mask the collet from unintentional inward movement.